Field of the Invention
The present invention relates to an accessory shoe device to which an accessory is attached, and an image pickup apparatus equipped with the accessory shoe device.
Description of the Related Art
As an image pickup apparatus, there has been known an image pickup apparatus equipped with an accessory shoe device to which a photographic accessory (hereinafter simply referred to as “the accessory”) can be attached. The accessory shoe device of the image pickup apparatus is provided with an engagement portion for attachment of an accessory.
As the accessory attachable to the accessory shoe device, there may be mentioned not only an external strobe device, but also an electronic viewfinder (external display device) provided with a small-sized liquid crystal screen. In an area of the engagement portion of the accessory shoe device to which the electronic viewfinder can be attached, there is provided a connection connector comprised of a plurality of connection terminals for attachment of the electronic viewfinder, in addition to a connection terminal for connection with the external strobe device. Thus, the accessory shoe device has a configuration in which the two kinds of accessories, i.e. the external strobe device and the electronic viewfinder, can be selectively attached to the single engagement portion.
The accessory shoe device for attachment of the external strobe device has a shape defined by JIS. JIS defines the shape of the engagement portion for engagement with a connector portion of an accessory and the positional relationship between the external strobe device and a synchronizer contact.
As for the electronic viewfinder, in recent years, there has been a tendency toward multi-polarization, i.e. an increased number of connection signal terminals for connection to an image pickup apparatus according to an increasing demand for an increase in the number of pixels and a higher frame rate. For this reason, an attempt has been made to perform multi-polarization of a connector for connection with the electronic viewfinder within the shape of the engagement portion of the accessory shoe device, but this is not easy due to restriction on space. Further, to perform multi-polarization of the connector for connection with the electronic viewfinder under conditions where space is restricted, positional accuracy in positioning of the accessory shoe and the connection connector in a pitch direction in which the terminals of the connection connector are arranged becomes more significant for achievement of normal electrical connection.
In view of this, there has been proposed an accessory shoe device having an accessory shoe and a connection connector integrally combined with each other (see Japanese Patent Laid-Open Publication No. 2015-141403).
In the accessory shoe device proposed in Japanese Patent Laid-Open Publication No. 2015-141403, since the accessory shoe and the signal terminal connector for connection with an electronic viewfinder are integrally combined with each other, it is possible to ensure the positional accuracy in positioning the accessory shoe and the signal terminal connector in the pitch direction in which the terminals of the signal terminal connector are arranged.
However, the unitized accessory shoe is required to be electrically connected to an image pickup apparatus (camera) body. For this reason, in order to connect a flexible circuit board having the accessory shoe mounted thereon to a main circuit board inside the image pickup apparatus (camera) body, the image pickup apparatus (camera) body has to be formed with an opening at a location close to an accessory shoe mount, for insertion of the flexible circuit board. In this configuration, however, there is a fear that water droplets or moisture from outside can enter the image pickup apparatus via a gap between the accessory shoe mount and the accessory shoe and a periphery of the opening through which the flexible substrate is inserted.